Quickstart

This example defines a one-time purchase that grants perpetual desktop access and permits three active license installations.

desktop-offer.ts

import { Access, Billing, Licensing, Offer, Purchase } from "@byfungsi/sapa";
import { Effect } from "effect";

export const desktopOffer = Effect.gen(function* () {
  const access = yield* Access.entitlements({
    entitlements: ["desktop.use"],
    duration: "perpetual",
  });

  const licensing = yield* Licensing.eligibility({
    entitlement: "desktop.use",
    activationLimit: 3,
  });

  const purchase = yield* Purchase.parse({
    key: "desktop.use",
    revision: 1,
    provides: [access, licensing],
  });
  const billing = yield* Billing.oneTime({
    price: { currency: "IDR", amount: 1_499_000n },
  });

  return yield* Offer.parse({
    key: "desktop.perpetual",
    revision: 1,
    purchase,
    billing,
  });
});

Run the pure definition program at an application boundary:

main.ts

import { Effect } from "effect";
import { desktopOffer } from "./desktop-offer.js";

const offer = await Effect.runPromise(desktopOffer);
console.log(offer.key, offer.revision);

What SAPA validates

• Definition keys and revisions have valid branded representations.
• The license entitlement is provided by the same purchase.
• Billing uses a supported variant.
• 1_499_000n is an exact minor-unit amount, not floating-point currency.
• Unknown or excess fields fail at strict workflow boundaries.

Definition versus execution

Offer.parse validates immutable commercial terms. It does not perform network or persistence I/O. Durable registration and checkout operations require a Sapa Layer supplied by the host application. See runtime composition.